The field of the invention is machine elements and mechanisms and the invention is particularly concerned with adjustable hand levers. The state of the art may be ascertained by reference to U.S. Pat. Nos. 124,721; 262,519; 445,558 and 750,287.
There is a need in the field of hand operated levers for:
1. concrete foundation form pulling; PA0 2. counterweight lifting from a forklift; PA0 3. crate and box turnover and flipping; PA0 4. demolishing, prying and large nail pulling PA0 5. drainage gate lifting; PA0 6. elevator installation; PA0 7. fence post extraction; PA0 8. heavy object lifting such as walk-in coolers and freezers, auto engines, auto transmissions, castings, valves and computers; PA0 9. longshore hook-up of beams and bundle pipe; PA0 10. manhole cover lifting; PA0 11. metal fabrication lifting and alignment; PA0 12. oil field lifting; PA0 13. pipe line lifting; PA0 14. porch, step and sidewalk leveling; PA0 15. railroad tie lifting; PA0 16. safe moving; PA0 17. sign post extraction; PA0 18. tent stake pulling; PA0 19. timber lifting and rolling; PA0 20. trailer tongue lifting; PA0 21. tree root and stump extraction; PA0 22. buried utility pipe extraction; PA0 23. water well pipe extraction; and PA0 24. wood floor removal.
In order to carry out the above functions, it is necessary for the adjustable hand lever to be light in weight, vertically adjustable, variable in the force applied, easily dismantled and reassembled and low in cost. None of the prior art adjustable hand levers meet these requirements.